Radiosignaling



May 1, 1928.

1,668,261 R. H. BELL RADIOSIGNALING Filed Dec. 2?, 1923 FIGURE 4 INVENTOR ATTORNEY Patented lVlay 1,1928. 1,668,261

UNITED STATES PATENT OFFICE.

RICHARD H. BELL, SANTA CLARA, CALIFORNIA. I I

Application filed December 27, 1923. Serial No. 682,972.

It is the object of the invention to provide ner similar to coil 7 and by-means of which a simple, practical and highly etficient methsimilar results are obtained. d and means of controllingthe electrical In Figure 3 a combination is shown in impulses set up in wireless telephony or tewhich both a secondary coil 9 and a secondlegraphy whereby torender a sending or reary mass 10 are used, and either one or the 00 ceiving apparatus highly selective as to wave other operated as desired.

length and delicately a justable as to ampli- Another embodiment of the invention is fication, and one that will also increase the shown in Figure 4, wherein two secondary resonance and clearness of signals. elements 11 and 12 are used in conjunction 10 In the drawing: with primary coil 4, the end 13 of the sec- 65 Figure 1 is a diagrammatical illustration ondary coil 12 being connected to the ground of areceiving set embodying my invention. terminal 6 of the set, and one of the pri- Figure 2 is a 'diagrammatical illustration mary terminals as 14, connected to the terof another embodiment of my invention. minal5 of the set. In this form one end of 15 Figure 3 is a diagrammatical illustration the primary coil as 15 is left open and con- 70 of still another embodiment of the inventact made with the aerial 2 by the slider 4:. tion. Also one end of the secondary 12, as at 16, is Figure 4 is a diagrammatical illustration left open. This arrangement permits, perof another embodiment of the invention. ha 5, even finer adjustment than the forms In carrying out my invention in what is be ore disclosed since different adjustments 7 perhaps t e simplest form in a wireless remay be made relative to the one primary coil. oeiving set, I provide a simple vacuum tube Attention is particularly called to the fact non-regenerative receiving set indicated genthat one end of the secondary coil is grounderally by the numeral 1, all the parts repreed together with the other part of the cirsented being situated in and belonging to the cuit, butthe other end of the secondary being set. 1 free and one end of the primary being free At 2 I show the aerial grounded at 3 there results an open circuit between 4 and through the primary winding 4 of the cou- 12 and this is used in combination with elepler in the set, the slider being indicated at ment 11 or not as desired. 30 4: and the aerial and ground terminals of The successful operation of this invention the set being indicated at 5 and 6 respecdepends apparently upon the reaction of tively. the electrical currents flowing through the In the primary winding 4 is slidably inprimary coil upon the secondary element, serted a secondary winding 7, having no meand consequently it is immaterial whether tallic connections with anypart of the ciror not the said secondary be placed within cuit of aerial or set; This secondary coil 7, the primary or not. It is only necessary that in other Words, is situated in the primary the secondary be an open circuited coil or coil 4 with simply an air space between the a mass of some suitable metallic substance two elements. 7 arranged in proximity to the primary coi'l When the set is in operation, a movement and movable lengthwise with relation thereof the secondary coil longitudinally or otherto or in such a. manner as to cut through the wise, but always so as to cut through the lines of magnetic force of the primary. lines of magnetic force emanating from the The action between the primary and secprimary coil,infiuences the electrical impulses onda-ryis similar to the action of a chokepassing through the primary coil in such a coil used in alternating circuits but instead W0 manner as to not only amplify the signals of an iron core copper, brass, silver or gold, but to also accurately and delicately control or a coil made of any of these metals is prefthe wave length, serving as an adjustment erably used. However, it is not exactly the supplementary to the usual control on the same for the effect is seen also in incomplete primary coiland such other devices as may or open circuits as shown in Figure 4. Iron be inserted in either the aerial or set circuits. might also be used or any other metal, simple In Figure 2 a variation of this structure or composite. but the action does not appear is shown in which a metallic mass 8 (prefto be as good. erably copper in hollow cylindrical form) is The reaction obtained by arranging the 56 used as a secondary and operated in a mansecondary in suitable relation to the primary iii ' generative hook-up,

be applied to regenerative sets with improved results.

The above principle may. evidently plied to conjunction with any'receiving or sending be apset whatever.

' It is to be understood, of course, that while I have herein shown and described certain forms of the invention. changes in form,

construction, and method of operation may be made within the scope of the appended claims.

I claim V v V 1. In a radio receiving circuit having an aerial and a detector circuit including a aerial circuits alone and used in three electrode tube, a primary coil having one end connected to the input of said tube and having its opposite end open, a secondary coil inductively coupled to said rimary coil and having one end connecte to the grounded filament circuit of the tube and having its opposite end open, andmeans .or adjustably connecting said aerial to the primary coil. 7

2. In a radio receiving circuit having an aerial and a detector circuit including a three electrode tube, a primary coil having one end connected to the input of said tube and having its opposite end open, a secondary coil inductively coupled to said 7 ri- 'mary coil and having one end connected to the grounded filament circuit of the tube and having its opposite end open, means for ad justably connecting said aerial to the primary coil and a with the primary coil and adjustable relative'ly to the secondary coil. 7 v

RICHARD H. BELL.

metallic member associated 

